Lawmakers have plenty of questions for Lois Lerner, the IRS official who ordered the targeting of conservative groups to stop, concerning her past statements. She said she did nothing wrong, but invoked her Fifth Amendment rights.

IRS official Lois Lerner pauses during a House Oversight and Government Reform Committee hearing on Capitol Hill in Washington, Wednesday, to investigate the extra scrutiny IRS gave to Tea Party and other conservative groups that applied for tax-exempt status. Lerner told the committee she did nothing wrong and then invoked her Fifth Amendment rights.

Lois Lerner, the Internal Revenue Service official at the center of the storm over the agency’s targeting of conservative political groups, invoked her Fifth Amendment rights against self-incrimination Wednesday and declined to testify at a House hearing on the matter.

Why did she do that?

Many on the right assume she did so because she is covering up criminal activity. Twitter was aflame with comments noting that she is a registered Democrat and should be fired.

Lerner, however, denies she did anything wrong. In brief comments before the House Oversight and Government Reform Committee prior to her invocation of the Fifth, she said, “I have not broken any laws. I have not violated any IRS rules or regulations, and I have not provided false information to this or any other committee,” said Lerner.

The committee chairman, Rep. Darryl Issa (R) of California, said she was entitled to exercise her right to refuse to speak.

“There can be no question that we have to respect it. Additionally, her assertion is not to be viewed or used during this hearing to make any determination plus or minus as to actions that were taken,” Representative Issa said.

Lerner’s particular problem is that committee members and others have questions about her past statements as to when she found out about the IRS targeting of key words such as “tea party” when investigating the tax exempt status of 501(c)(4) organizations.

Earlier this month she told journalists she had learned of the practice from news reports in early 2012. But according to the just-released Inspector General report on the issue, Lerner, head of the IRS division on tax-exempt organizations, found out her employees were targeting conservative groups in June, 2011.

She ordered the targeting to stop, but it gradually returned with slightly broader key word searches. Members want to know why it wasn’t killed immediately.

Oversight panel members also want to know whether she misled congressional investigators about her knowledge of the targeting.

Staff members of the Issa-led panel talked with Lerner and other IRS officials in 2012 following complaints from some conservative organizations that they were having trouble with the IRS. At the time Lerner did not mention the targeting. Nor did she talk about it with staff members of a House Ways and Means subcommittee who were looking at the same issue and who questioned her early last year.

Given the contradictions between her words and the public record, it’s perhaps not surprising that Lerner declined to discuss the issue in the televised glare of a politically-charged hearing.

So why does she still have an IRS job? It might be because it’s not easy to fire her, or most other government workers that don’t fill a politically-appointed job.

As David Nather and Rachel Bade note at Politico, “Most employees involved in the targeting program are covered by protections for federal workers that could drag out the termination process.”

If the Obama administration decides it needs to ditch Lerner, its best chance might be to just ask her to resign and see if she goes along. The outgoing acting director of the agency, Steven Miller, was a career official who could have dug in if he’d wanted to. But when Treasury Secretary Jack Lew asked him to quit, he did.